An harmonic 1D-element for nonlinear analysis of axisymmetric structures: the case of hot rolling

Work rolls in hot rolling mills are subjected to thermal and mechanical loads that could affect the surface integrity of the roll. To estimate the roll lifetime, the thermomechanical behaviour of the work roll was recently studied adopting a 2D plain strain model. Nevertheless, even this 2D approach requires an extremely long computational time, which allows only thermal loads to be considered in the mechanical analysis. Work rolls are axisymmetric structures subjected to cyclic non axisymmetric thermal and mechanical loads, thus, to further reduce the dimension of the problem, an original 1D semi-analytical thermal and mechanical finite element is developed. Transient thermal and mechanical non linear analysis of a work roll is performed according to the initial stress method. The localized mechanical loads, which represents interaction of the work roll with the strip material and with the back up roll, are also taken into account.